More Documentation of File Size

[bollwyvl]

Probably need some information about how using Jyve can pose challenges to hosting and serving.

The kernel runtimes (except for JS) are very large on disk and on the wire, and we've barely gotten started with the Children of WebAssembly (#12).

A number of these runtimes carry large standard libraries ported directly into their "native" environment (e.g. Brython), or are simply very full-featured (e.g. TypeScript, p5) and don't rely on any external libraries that might already be covered by vendors~main.